Mind reader's ability, briefly (3)
I believe the answer is:
esp
'mind reader's ability briefly' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for esp that I've seen before include "Apparent power to perceive things that others can't, in short" , "Extrasensory perception (abbrev.)" , "Apparent power to perceive things that others can't, initially" , "Initially, clairvoyance or telepathy" , "Second sight (abbr)" .)